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restart apache only if config works
making lots of configurations to apache and restarting the server only to find it broken just plain sucks.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Create a QR code image in MECARD format
Add the QR code image on your webpage, business card ., etc, so people can scan it and quick add to their Contact Address Book. Tested on iPhone with QRreader.

Monitor bandwidth by pid
Nethogs is a useful tool for monitor bandwidth consumption by pid. Tested on Debian an CentOs

ROT13 using the tr command

"at" command w/o the resource usage/competition issues
EXAMPLES jb "next sun 12pm" "/bin/sh ~you/1.sh" & jb "2010-08-29 12:00:00" "~you/1.sh" & jb "29aug2010 gmt" ". ~you/1.sh" & jb 12:00p.m. "nohup ./1.sh" & jb 1min "echo stop!" & SEE ALSO parsedate(3) strftime(3)

Grep for regular expression globally, list files and positions.
Grep for expression globally, list files and positions. "Hirn" is a nice german crib meaning "Brain". :-) Afterwards you can edit the line you want with "vi ./p_common/common_main.pbt +1550"

Prevent shell autologout
Unset TMOUT or set it to 0 in order to prevent shell autologout. TMOUT is the number of seconds after which the present shell will be killed if it has been idle for that long.


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